We have also performed robustness tests of the FTI
results, and showed that the bounds could be sensitive
to the tapering frequency, depending on the parameters of the signal
being analyzed. For very low total-mass systems like the BNS
GW170817, the tapering frequency lies outside the frequency band where
the majority of the SNR is accumulated, thus the bounds are not
expected to change. On the other hand, for high–total-mass BBH systems,
like GW190814 and GW190412, the bounds on the deviation parameters can change. More specifically,
bounds on deviation parameters that are measured with an accuracy of few tens of percent or less,
may change by a factor \(2\mbox{--}5\) , depending on the binary's parameters, when the tapering
frequency spans the last \(3\mbox{--}4\)  GW cycles before the (2,2)-mode's peak. These results suggest to
go beyond the choice of the tapering frequency adopted so far in Refs. [1]}, [2]}, [3]}, [4]}, [5]}, where it was fixed
to a specific value to compare with the complimentary analysis provided by the TIGER framework [6]}.
In order to optimize the GR test with the FTI and exploit the full SNR accumulated during the inspiral, up
to merger, comprehensive studies would need to be undertaken to determine the best choice of the
tapering frequency as a function of the binary's properties and the accumulated SNR.
By contrast, we have shown that the bounds are marginally affected by the use of a different but similarly accurate waveform model, e.g.,
the state-of-the-art aligned-spin (phenomenological) pPhenomX model, instead of pSEOBNR.
